A spokesman for Ms Gambaro said that was all she would say on the matter.

Ms Gambaro, who held Brisbane with a margin of just 3.15 per cent, had faced a spirited Labor campaign spearheaded by its army major candidate, Pat O'Neill, prior to her retirement announcement on Wednesday.

One LNP source said Ms Gambaro, who had 15 years of parliamentary experience, was bitterly disappointed to have missed out on a promotion in two successive front bench reshuffles.

"She went into meltdown last year when she didn't get a promotion and it happened again this year (when Prime Minister Malcolm Turnbull appointed his new ministry)," the source said.

"The timing of this is appalling.

"Brisbane was not in play before this, but now she's all but handing it to Labor.

Trevor Evans, the Liberal National Party candidate for the federal seat of Brisbane.

Photo: Supplied

"She's f---ed the party, crucified the party, because there's no time for a new candidate to get the name recognition."

Another LNP source described Ms Gambaro's decision as a "massive dummy spit".

While former premier Campbell Newman was considered an unlikely starter for LNP preselection in Brisbane, former state MP Robert Cavallucci (right) was considering his options.

Photo: Harrison Saragossi

"Teresa was telling everyone in the party how she had the name recognition and was the only person who could win Brisbane," the source said.

"This is just self-interest of the highest order.

She's f---ed the party, crucified the party

Anonymous LNP source

"We've got nobody palatable with name recognition to win the seat.

"Campbell Newman has the name recognition, but he's not palatable."

Comment was sought from Mr Newman, but the former Queensland premier was considered by party sources to be an unlikely candidate, given his stated enjoyment of post-political life.

In her statement, Ms Gambaro said: "The time has come to be available to my family and to pursue other opportunities."

Mr O'Neill, the Labor candidate, said Ms Gambaro's decision to bow out of the campaign would not affect his campaign.

"This has never been a fight against Teresa Gambaro, it's been a fight against what we see as an increasingly out-of-touch LNP government whose values aren't shared by the people of Brisbane," he said.

"…I've always got along well with Teresa and I wish her well in whatever she does next, her and her family.

"She's always been nice to me and my mum, when my mum was principal at New Farm State School, but no, this doesn't change the campaign."

The attention will now turn to who will replace Ms Gambaro on the ballot paper for the LNP.

National Retail Association chief executive Trevor Evans was understood to be the frontrunner for preselection.